JP2006144119A - Layered product for sputtering aluminum-neodymium alloys - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a layered product for sputtering an Al-Nd alloy capable of reducing warp caused by bonding or film deposition of an Al-Nd alloy thin film of the assembly in which an Al-Nd alloy sputtering target and a backing plate are brazed to each other, and performing stable film deposition over a long time. <P>SOLUTION: In the layered product, an Al-Nd alloy sputtering target formed of an Al alloy having a Nd content of 0.1 to 3 atomic%, and a backing plate are brazed to each other. The assembly has an average coefficient of linear expansion A at temperatures of 25 to 100°C, and the backing plate has an average coefficient of linear expansion B at temperatures of 25 to 100°C. The A and B satisfy the inequalities -0.15≤(B-A)/A≤0.15. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a laminate for sputtering an Al—Nd alloy, and in particular, a laminate in which an Al—Nd alloy sputtering target material and a support are brazed, and includes bonding and Al—Nd alloy thin film. The present invention relates to an Al alloy sputtering laminate that can suppress the warpage of the laminate that occurs during film formation (sputtering film formation) and can perform stable film formation over a long period of time.

  Sputtering is generally used to form thin films that constitute liquid crystal displays, organic EL displays, etc., which are formed for televisions, notebook computers, other monitors, and wiring films in the optical recording field and semiconductor field. . In the sputtering method, a plasma discharge is formed between a substrate and a sputtering target material (hereinafter referred to as a target material), and a gas ionized by the plasma discharge is collided with the target material to knock out atoms of the target material. This is a method for producing a thin film by depositing on a substrate, and has a merit that a thin film having the same composition as that of a target material can be formed unlike a vacuum vapor deposition method or an AIP method.

  As the target material used in this sputtering method, a flat plate having a rectangular shape or a disk shape is generally used, and the target is used as a support (also called a cooling plate or a backing plate) for the purpose of cooling or supporting the target. In general, it is used in a brazed state.

  By the way, as described above, the support is intended to cool the target heated during the film formation, and therefore, the support made of Cu or Cu alloy having high thermal conductivity is generally used. On the other hand, the target material attached to the support is made of a metal material corresponding to the thin film to be formed. For example, a metal material such as Al, Al alloy, Mo, Ta, Ti different from the support may be used. Many.

  However, such a laminate obtained by brazing different metal materials is likely to warp as shown in FIG. 1 and requires correction. In addition, when film formation is performed using the layered body thus corrected, stress is generated because heating and cooling are repeated. Therefore, it is necessary to repeat film formation, occurrence of warpage and correction of the laminate many times, not only the operation becomes complicated, but cracks occur in the brazing material 3 between the target material 1 and the support 2, There is also a problem that the target material and the support are separated before the target material is consumed, and the film cannot be repeatedly formed.

  As what solved the problem of the laminated body obtained by brazing a target and a support (backing plate), for example, in patent documents 1, a target material and a backing plate are joined via a bonding material, There has been proposed a structure in which a concave portion for a bonding material is provided on the backing plate and a communication concave portion communicating with the concave portion is formed on the outer peripheral wall of the concave portion. It is shown that the warping of the target material does not occur even when the bonding material is solidified and contracted by using such a structure. However, this technique does not have a problem of peeling of the bonding part (the brazing material), and there is a problem that a complicated shape must be prepared as a backing plate.

  In Patent Document 2, if a plate material having a coefficient of thermal expansion larger than that of a sputtering target and a small plate material are respectively arranged and integrated on one side of the backing plate, the backing plate is prevented from warping due to a temperature change, and a supporting target is provided. It has been shown that the same thermal expansion characteristics can be imparted, and warping and cracking of the target, peeling of the brazed portion, etc. can be suppressed. However, this technique also has a demerit that the structure of the backing plate is complicated.

Patent Document 3 proposes that the difference between the linear expansion coefficients is reduced by forming the target and the backing plate with an Al alloy. However, in the combination of the target and the backing plate in this technology, when an Al—Nd alloy is used as the target, the difference in thermal expansion coefficient between the two is not sufficiently reduced, and the crack of the brazing material is surely suppressed. Can not do it.
JP 2003-183822 A Japanese Patent Laid-Open No. 08-246144 Japanese Patent Laid-Open No. 10-046327

  The present invention has been made in view of the above circumstances, and its purpose is to provide a warped or Al-Nd alloy thin film of a laminate in which an Al alloy sputtering target material containing Nd and a support are brazed. An Al—Nd alloy sputtering laminate that suppresses the stress caused by film formation (sputtering film formation), eliminates the correction of warping, and can perform stable film formation over a long period of time is provided. There is to do.

An Al—Nd alloy sputtering laminate according to the present invention is a laminate in which an Al—Nd alloy sputtering target material containing 0.1 to 3 atomic% of Nd and a support are brazed, and the Al—Nd The alloy sputtering target material is characterized in that the average linear expansion coefficient A of 25 to 100 ° C. and the average linear expansion coefficient B of 25 to 100 ° C. of the support satisfy the following formula (1).
−0.15 ≦ (BA) /A≦0.15 (1)

  The average coefficient of linear expansion at 25 to 100 ° C. was measured as specified in JIS K 7197 “Test method for linear expansion coefficient by thermomechanical analysis of plastics” using a TMA 8140 model manufactured by Rigaku Corporation. is there.

  As the support constituting the laminate, one made of an Al alloy is preferable, and one made of an Al alloy defined by JIS standard A5052 or A6061 is particularly preferable.

  In particular, it is desirable to use the support made of the same Al alloy as the Al—Nd alloy sputtering target material because the above formula (1) can be easily achieved.

  According to the present invention, since a warp caused by bonding or film formation (sputtering film formation) of an Al—Nd alloy thin film of a laminate in which an Al—Nd alloy sputtering target material and a support are brazed can be suppressed, warpage is prevented. It is possible to omit the correction, and cracking and peeling of the brazing material joining the target material and the support are suppressed, and a stable film forming operation can be performed over a long period of time.

  The inventors have warped a laminated body (hereinafter sometimes simply called a laminated body) in which an Al alloy sputtering target material and a support are brazed by heating at the time of bonding or film formation and subsequent cooling. It is possible to suppress the occurrence of the warpage by suppressing the occurrence of the warpage, and to suppress the cracking / peeling of the brazing material between the target material and the support due to the occurrence of the warpage and the repetition of the correction. We conducted intensive research to realize a laminate that can perform stable film formation.

As a result, the difference between the average linear expansion coefficient A of 25 to 100 ° C. of the Al—Nd alloy sputtering target material in the laminate and the average linear expansion coefficient B of 25 to 100 ° C. of the support is represented by the following formula (1 ), The inventors have found that the content of A should be −15% or more and 15% or less with respect to A, and have arrived at the present invention.
−0.15 ≦ (BA) /A≦0.15 (1)

  The laminated body of this invention should just be what the average linear expansion coefficient of 25-100 degreeC of an Al-Nd alloy sputtering target material and a support satisfy | fills said Formula (1), and about the detailed material of a support, etc. However, in order to efficiently obtain a laminate satisfying the above formula (1), it is effective to control the average linear expansion coefficient of the support according to the Al alloy sputtering target material to be used, A support made of an Al alloy is preferably used. As the Al alloy, those made of existing Al alloys can be used, and among them, those made of JIS standard A5000 series or A6000 series Al alloys are preferably used. What consists of Al alloy prescribed | regulated by A6061 is preferable.

  From the viewpoint of reducing the difference between the average linear expansion coefficients of 25 to 100 ° C. between the Al—Nd alloy sputtering target material and the support, the Al—Nd alloy sputtering target material and the support are made of the same Al alloy. A laminate is particularly preferred.

  Although these Al alloys have a lower thermal conductivity than Cu-based materials that have been conventionally used, they can sufficiently exhibit the function of cooling the brazed target.

  The support in the laminate of the present invention may have a structure in which the inside cools the target, and the cooling structure may be a generally adopted structure. As an example, two members constituting the support may be joined by, for example, welding or friction diffusion bonding to form a coolant channel inside the support. In addition, equipment such as a power supply, installation parts for the film forming apparatus, and the like may be attached to the laminate.

  As a manufacturing method of the Al—Nd alloy sputtering target containing 0.1 to 3 atomic% of Nd constituting the laminate, for example, it can be manufactured by a vacuum melting / casting method, a spray forming method, a powder sintering method, or the like. Among them, those manufactured by the spray forming method are recommended. This is because, when produced by the spray forming method, even when an alloy element is contained, a uniform material can be obtained by uniformly dissolving or dispersing in Al as a matrix phase.

When the sputtering target is manufactured by the spray forming method, for example, a dissolved material is dropped from a nozzle having a diameter of several mm, and, for example, N ₂ gas is blown in the middle of dropping to pulverize the material. An intermediate material (density: about 50 to 60%) called a preform is formed before the material is completely solidified. Then, after the intermediate material is densified with a HIP apparatus, it is forged into a plate-like metal material, and further rolled so that the plate thickness is substantially the same as the target (in addition, the above HIP, forging, rolling) General conditions can be adopted for other manufacturing process conditions such as).

  The laminate of the present invention is used for film formation in a state where the Al alloy sputtering target is brazed to the plane of the support plate, but the brazing material and brazing method used at that time are also particularly limited. Instead, general materials and methods can be employed. Even when a general brazing material such as indium, lead-tin solder, tin-zinc solder, or the like is used as the brazing material, the film formation can be performed repeatedly and satisfactorily.

The laminate of the present invention is not limited in its shape and size, and can be applied to various shapes such as a quadrilateral shape and a disk shape depending on the shape and size of the target. Since cracks and the like become more prominent as the size of the laminate increases, particularly when the present invention is applied to a large laminate in which a brazed portion for joining a target occupies 0.25 m ² or more, the cracks in the brazing material Can be remarkably suppressed.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited by the following examples, but may be appropriately modified within a range that can meet the purpose described above and below. It is also possible to implement, and they are all included in the technical scope of the present invention.

  As a sputtering target, an Al-2 atomic% Nd target (size: 400 mm × 500 mm) was prepared. Further, as a support (cooling plate), supports (size: 420 mm × 520 mm) made of various types of materials shown in Table 1 were prepared. The average linear expansion coefficient of 25 to 100 ° C. of each of the Al-2 atomic% Nd target and the support (cooling plate) was used as a device using TMA8140 type manufactured by Rigaku Corporation. JIS K 7197 “Plastic heat Measured as prescribed in "Method of testing linear expansion coefficient by mechanical analysis", the average linear expansion coefficient (A) of the target material of 25 to 100 ° C and the average linear expansion coefficient (B) of 25 to 100 ° C of the support. (BA) / A was determined from the value of. The results are also shown in Table 1.

  From Table 1, No. 1-3, the relationship between the average linear expansion coefficients of the Al—Nd alloy target and the support (cooling plate) satisfies the requirements specified in the present invention. 4 does not satisfy this requirement, and it can be seen that the difference in average linear expansion coefficient between the Al—Nd alloy target and the support (cooling plate) is large.

  Next, the degree of warpage of the laminate obtained by bonding the Al—Nd alloy target shown in Table 1 and a support (cooling plate) was examined. Specifically, tin-zinc solder was used as a brazing material, heated to 250 ° C. to bond the target and support in Table 1, and the warpage of the obtained laminate was measured at the position shown in FIG. The results are also shown in Table 1 (measurement positions in Table 1: L1, L2,... Indicate the measurement positions in FIG. 2).

  It should be noted that the amount of warpage at the measurement positions L1, L2, L3 exceeds 3.5 mm, the amount of warpage at the measurement positions W1, W2, W3 exceeds 2.0 mm, and the amount of warpage at the measurement positions D1, D2 is 5.0 mm. A warp exceeding that is judged to have a large warp, and those within this are judged to have a small warp.

  From Table 1, it can be considered as follows. That is, No. 1 in Table 1. 1-4. The laminated body for sputtering of Al—Nd alloy comprising a combination of an Al—Nd alloy target and a support that satisfies the requirements of the present invention as in 1 to 3 does not need to be corrected with small warpage after bonding. No. that does not meet the requirements. It can be seen that the laminate of No. 4 needs to greatly correct the warpage after bonding.

It is the side view which showed typically the mode of the curvature of a laminated body. It is a top view which shows the measurement position of the curvature of the laminated body in the bonding test of an Example.

Explanation of symbols

1 target 2 support (cooling plate)
3 brazing material

Claims (5)

A laminate in which an Al—Nd alloy sputtering target material made of an Al alloy containing 0.1 to 3 atomic% of Nd and a support are brazed,
The average linear expansion coefficient A of 25-100 ° C. of the Al—Nd alloy sputtering target material and the average linear expansion coefficient B of 25-100 ° C. of the support are:
The laminated body for Al-Nd alloy sputtering characterized by satisfy | filling following formula (1).
−0.15 ≦ (BA) /A≦0.15 (1)   The laminate for sputtering an Al—Nd alloy according to claim 1, wherein the support is made of an Al alloy.   The said support body is a laminated body for Al-Nd alloy sputtering of Claim 2 which consists of Al alloy prescribed | regulated by A5052 of JIS specification.   The said support body is a laminated body for Al-Nd alloy sputtering of Claim 2 which consists of Al alloy prescribed | regulated by A6061 of JIS specification.   The laminate for sputtering an Al-Nd alloy according to claim 2, wherein the support is made of the same Al alloy as the Al-Nd alloy sputtering target material.

Images